/ Check-in [87a9fc50]
Login

Many hyperlinks are disabled.
Use anonymous login to enable hyperlinks.

Overview
Comment:Use an OP_NotFound opcode to cancel futile IN operators early. The current implementation is suboptimal because it always runs teh OP_NotFound. This still needs to be enhanced to only do the OP_NotFound if no results have been seen on the current loop.
Downloads: Tarball | ZIP archive | SQL archive
Timelines: family | ancestors | descendants | both | multikey-opt-idea
Files: files | file ages | folders
SHA3-256:87a9fc504f9a78caf7a7949cc7ada0a19d61bfab51bb49a00a1607194c116212
User & Date: drh 2018-06-05 15:16:25
Context
2018-06-05
20:45
Add the OP_IfNoHope and OP_SeekHit opcodes used to reduce the number of unnecessary sqlite3BtreeMovetoUnpacked() calls when checking for an early exit on IN-operator loops. Futher optimizations are likely possible here. check-in: 6bf251af user: drh tags: multikey-opt-idea
15:16
Use an OP_NotFound opcode to cancel futile IN operators early. The current implementation is suboptimal because it always runs teh OP_NotFound. This still needs to be enhanced to only do the OP_NotFound if no results have been seen on the current loop. check-in: 87a9fc50 user: drh tags: multikey-opt-idea
13:54
Merge trunk changes. check-in: 047295c5 user: drh tags: multikey-opt-idea
Changes
Hide Diffs Unified Diffs Ignore Whitespace Patch

Changes to src/where.c.

5080
5081
5082
5083
5084
5085
5086
5087

5088

5089
5090
5091
5092
5093
5094
5095
      struct InLoop *pIn;
      int j;
      sqlite3VdbeResolveLabel(v, pLevel->addrNxt);
      for(j=pLevel->u.in.nIn, pIn=&pLevel->u.in.aInLoop[j-1]; j>0; j--, pIn--){
        sqlite3VdbeJumpHere(v, pIn->addrInTop+1);
        if( pIn->eEndLoopOp!=OP_Noop ){
          if( pIn->nPrefix ){
            sqlite3VdbeAddOp3(v, OP_Noop, pLevel->iIdxCur,

                              pIn->iBase, pIn->nPrefix);

          }
          sqlite3VdbeAddOp2(v, pIn->eEndLoopOp, pIn->iCur, pIn->addrInTop);
          VdbeCoverage(v);
          VdbeCoverageIf(v, pIn->eEndLoopOp==OP_PrevIfOpen);
          VdbeCoverageIf(v, pIn->eEndLoopOp==OP_NextIfOpen);
        }
        sqlite3VdbeJumpHere(v, pIn->addrInTop-1);







|
>

>







5080
5081
5082
5083
5084
5085
5086
5087
5088
5089
5090
5091
5092
5093
5094
5095
5096
5097
      struct InLoop *pIn;
      int j;
      sqlite3VdbeResolveLabel(v, pLevel->addrNxt);
      for(j=pLevel->u.in.nIn, pIn=&pLevel->u.in.aInLoop[j-1]; j>0; j--, pIn--){
        sqlite3VdbeJumpHere(v, pIn->addrInTop+1);
        if( pIn->eEndLoopOp!=OP_Noop ){
          if( pIn->nPrefix ){
            sqlite3VdbeAddOp4Int(v, OP_NotFound, pLevel->iIdxCur,
                              sqlite3VdbeCurrentAddr(v)+2,
                              pIn->iBase, pIn->nPrefix);
            VdbeCoverage(v);
          }
          sqlite3VdbeAddOp2(v, pIn->eEndLoopOp, pIn->iCur, pIn->addrInTop);
          VdbeCoverage(v);
          VdbeCoverageIf(v, pIn->eEndLoopOp==OP_PrevIfOpen);
          VdbeCoverageIf(v, pIn->eEndLoopOp==OP_NextIfOpen);
        }
        sqlite3VdbeJumpHere(v, pIn->addrInTop-1);

Changes to src/wherecode.c.

588
589
590
591
592
593
594

595
596



597
598
599
600
601
602
603
            int iCol = aiMap ? aiMap[iMap++] : 0;
            pIn->addrInTop = sqlite3VdbeAddOp3(v,OP_Column,iTab, iCol, iOut);
          }
          sqlite3VdbeAddOp1(v, OP_IsNull, iOut); VdbeCoverage(v);
          if( i==iEq ){
            pIn->iCur = iTab;
            pIn->eEndLoopOp = bRev ? OP_PrevIfOpen : OP_NextIfOpen;

            pIn->iBase = iReg - i;
            pIn->nPrefix = i;



          }else{
            pIn->eEndLoopOp = OP_Noop;
          }
          pIn++;
        }
      }
    }else{







>
|
|
>
>
>







588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
            int iCol = aiMap ? aiMap[iMap++] : 0;
            pIn->addrInTop = sqlite3VdbeAddOp3(v,OP_Column,iTab, iCol, iOut);
          }
          sqlite3VdbeAddOp1(v, OP_IsNull, iOut); VdbeCoverage(v);
          if( i==iEq ){
            pIn->iCur = iTab;
            pIn->eEndLoopOp = bRev ? OP_PrevIfOpen : OP_NextIfOpen;
            if( (pLoop->wsFlags & WHERE_VIRTUALTABLE)==0 ){
              pIn->iBase = iReg - i;
              pIn->nPrefix = i;
            }else{
              pIn->nPrefix = 0;
            }
          }else{
            pIn->eEndLoopOp = OP_Noop;
          }
          pIn++;
        }
      }
    }else{